diff --git a/source/utilities.tex b/source/utilities.tex
index 9cedb5cf2f..402dbea68d 100644
--- a/source/utilities.tex
+++ b/source/utilities.tex
@@ -11053,7 +11053,7 @@
 \tcode{false} otherwise.
 \end{itemdescr}
 
-\indexlibrarymember{operator~}{bitset::reference}%
+\indexlibrarymember{operator\~{}}{bitset::reference}%
 \begin{itemdecl}
 constexpr bool reference::operator~() const noexcept;
 \end{itemdecl}